* include/ruby/ruby.h: introduce new flags for T_TYPEDDATA.
  * RUBY_TYPED_FREE_IMMEDIATELY: free the data given by DATA_PTR()
    with dfree function immediately.  Otherwise (default), the data
    freed at finalizaton point.
  * RUBY_TYPED_WB_PROTECTED: make this object with FL_WB_PROTECT
    (not shady).
* gc.c (obj_free): support RUBY_TYPED_FREE_IMMEDIATELY.



git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@43463 b2dd03c8-39d4-4d8f-98ff-823fe69b080e